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-rw-r--r--drivers/base/power/main.c344
1 files changed, 340 insertions, 4 deletions
diff --git a/drivers/base/power/main.c b/drivers/base/power/main.c
index eb9f38d0aa58..0ab4ab21f564 100644
--- a/drivers/base/power/main.c
+++ b/drivers/base/power/main.c
@@ -20,19 +20,24 @@
20 */ 20 */
21 21
22#include <linux/device.h> 22#include <linux/device.h>
23#include <linux/kallsyms.h>
23#include <linux/mutex.h> 24#include <linux/mutex.h>
25#include <linux/pm.h>
26#include <linux/resume-trace.h>
24 27
28#include "../base.h"
25#include "power.h" 29#include "power.h"
26 30
27LIST_HEAD(dpm_active); 31LIST_HEAD(dpm_active);
28LIST_HEAD(dpm_off); 32static LIST_HEAD(dpm_off);
29LIST_HEAD(dpm_off_irq); 33static LIST_HEAD(dpm_off_irq);
30 34
31DEFINE_MUTEX(dpm_mtx); 35static DEFINE_MUTEX(dpm_mtx);
32DEFINE_MUTEX(dpm_list_mtx); 36static DEFINE_MUTEX(dpm_list_mtx);
33 37
34int (*platform_enable_wakeup)(struct device *dev, int is_on); 38int (*platform_enable_wakeup)(struct device *dev, int is_on);
35 39
40
36int device_pm_add(struct device *dev) 41int device_pm_add(struct device *dev)
37{ 42{
38 int error; 43 int error;
@@ -61,3 +66,334 @@ void device_pm_remove(struct device *dev)
61} 66}
62 67
63 68
69/*------------------------- Resume routines -------------------------*/
70
71/**
72 * resume_device - Restore state for one device.
73 * @dev: Device.
74 *
75 */
76
77static int resume_device(struct device * dev)
78{
79 int error = 0;
80
81 TRACE_DEVICE(dev);
82 TRACE_RESUME(0);
83
84 down(&dev->sem);
85
86 if (dev->bus && dev->bus->resume) {
87 dev_dbg(dev,"resuming\n");
88 error = dev->bus->resume(dev);
89 }
90
91 if (!error && dev->type && dev->type->resume) {
92 dev_dbg(dev,"resuming\n");
93 error = dev->type->resume(dev);
94 }
95
96 if (!error && dev->class && dev->class->resume) {
97 dev_dbg(dev,"class resume\n");
98 error = dev->class->resume(dev);
99 }
100
101 up(&dev->sem);
102
103 TRACE_RESUME(error);
104 return error;
105}
106
107
108static int resume_device_early(struct device * dev)
109{
110 int error = 0;
111
112 TRACE_DEVICE(dev);
113 TRACE_RESUME(0);
114 if (dev->bus && dev->bus->resume_early) {
115 dev_dbg(dev,"EARLY resume\n");
116 error = dev->bus->resume_early(dev);
117 }
118 TRACE_RESUME(error);
119 return error;
120}
121
122/*
123 * Resume the devices that have either not gone through
124 * the late suspend, or that did go through it but also
125 * went through the early resume
126 */
127static void dpm_resume(void)
128{
129 mutex_lock(&dpm_list_mtx);
130 while(!list_empty(&dpm_off)) {
131 struct list_head * entry = dpm_off.next;
132 struct device * dev = to_device(entry);
133
134 get_device(dev);
135 list_move_tail(entry, &dpm_active);
136
137 mutex_unlock(&dpm_list_mtx);
138 resume_device(dev);
139 mutex_lock(&dpm_list_mtx);
140 put_device(dev);
141 }
142 mutex_unlock(&dpm_list_mtx);
143}
144
145
146/**
147 * device_resume - Restore state of each device in system.
148 *
149 * Walk the dpm_off list, remove each entry, resume the device,
150 * then add it to the dpm_active list.
151 */
152
153void device_resume(void)
154{
155 might_sleep();
156 mutex_lock(&dpm_mtx);
157 dpm_resume();
158 mutex_unlock(&dpm_mtx);
159}
160
161EXPORT_SYMBOL_GPL(device_resume);
162
163
164/**
165 * dpm_power_up - Power on some devices.
166 *
167 * Walk the dpm_off_irq list and power each device up. This
168 * is used for devices that required they be powered down with
169 * interrupts disabled. As devices are powered on, they are moved
170 * to the dpm_active list.
171 *
172 * Interrupts must be disabled when calling this.
173 */
174
175static void dpm_power_up(void)
176{
177 while(!list_empty(&dpm_off_irq)) {
178 struct list_head * entry = dpm_off_irq.next;
179 struct device * dev = to_device(entry);
180
181 list_move_tail(entry, &dpm_off);
182 resume_device_early(dev);
183 }
184}
185
186
187/**
188 * device_power_up - Turn on all devices that need special attention.
189 *
190 * Power on system devices then devices that required we shut them down
191 * with interrupts disabled.
192 * Called with interrupts disabled.
193 */
194
195void device_power_up(void)
196{
197 sysdev_resume();
198 dpm_power_up();
199}
200
201EXPORT_SYMBOL_GPL(device_power_up);
202
203
204/*------------------------- Suspend routines -------------------------*/
205
206/*
207 * The entries in the dpm_active list are in a depth first order, simply
208 * because children are guaranteed to be discovered after parents, and
209 * are inserted at the back of the list on discovery.
210 *
211 * All list on the suspend path are done in reverse order, so we operate
212 * on the leaves of the device tree (or forests, depending on how you want
213 * to look at it ;) first. As nodes are removed from the back of the list,
214 * they are inserted into the front of their destintation lists.
215 *
216 * Things are the reverse on the resume path - iterations are done in
217 * forward order, and nodes are inserted at the back of their destination
218 * lists. This way, the ancestors will be accessed before their descendents.
219 */
220
221static inline char *suspend_verb(u32 event)
222{
223 switch (event) {
224 case PM_EVENT_SUSPEND: return "suspend";
225 case PM_EVENT_FREEZE: return "freeze";
226 case PM_EVENT_PRETHAW: return "prethaw";
227 default: return "(unknown suspend event)";
228 }
229}
230
231
232static void
233suspend_device_dbg(struct device *dev, pm_message_t state, char *info)
234{
235 dev_dbg(dev, "%s%s%s\n", info, suspend_verb(state.event),
236 ((state.event == PM_EVENT_SUSPEND) && device_may_wakeup(dev)) ?
237 ", may wakeup" : "");
238}
239
240/**
241 * suspend_device - Save state of one device.
242 * @dev: Device.
243 * @state: Power state device is entering.
244 */
245
246static int suspend_device(struct device * dev, pm_message_t state)
247{
248 int error = 0;
249
250 down(&dev->sem);
251 if (dev->power.power_state.event) {
252 dev_dbg(dev, "PM: suspend %d-->%d\n",
253 dev->power.power_state.event, state.event);
254 }
255
256 if (dev->class && dev->class->suspend) {
257 suspend_device_dbg(dev, state, "class ");
258 error = dev->class->suspend(dev, state);
259 suspend_report_result(dev->class->suspend, error);
260 }
261
262 if (!error && dev->type && dev->type->suspend) {
263 suspend_device_dbg(dev, state, "type ");
264 error = dev->type->suspend(dev, state);
265 suspend_report_result(dev->type->suspend, error);
266 }
267
268 if (!error && dev->bus && dev->bus->suspend) {
269 suspend_device_dbg(dev, state, "");
270 error = dev->bus->suspend(dev, state);
271 suspend_report_result(dev->bus->suspend, error);
272 }
273 up(&dev->sem);
274 return error;
275}
276
277
278/*
279 * This is called with interrupts off, only a single CPU
280 * running. We can't acquire a mutex or semaphore (and we don't
281 * need the protection)
282 */
283static int suspend_device_late(struct device *dev, pm_message_t state)
284{
285 int error = 0;
286
287 if (dev->bus && dev->bus->suspend_late) {
288 suspend_device_dbg(dev, state, "LATE ");
289 error = dev->bus->suspend_late(dev, state);
290 suspend_report_result(dev->bus->suspend_late, error);
291 }
292 return error;
293}
294
295/**
296 * device_suspend - Save state and stop all devices in system.
297 * @state: Power state to put each device in.
298 *
299 * Walk the dpm_active list, call ->suspend() for each device, and move
300 * it to the dpm_off list.
301 *
302 * (For historical reasons, if it returns -EAGAIN, that used to mean
303 * that the device would be called again with interrupts disabled.
304 * These days, we use the "suspend_late()" callback for that, so we
305 * print a warning and consider it an error).
306 *
307 * If we get a different error, try and back out.
308 *
309 * If we hit a failure with any of the devices, call device_resume()
310 * above to bring the suspended devices back to life.
311 *
312 */
313
314int device_suspend(pm_message_t state)
315{
316 int error = 0;
317
318 might_sleep();
319 mutex_lock(&dpm_mtx);
320 mutex_lock(&dpm_list_mtx);
321 while (!list_empty(&dpm_active) && error == 0) {
322 struct list_head * entry = dpm_active.prev;
323 struct device * dev = to_device(entry);
324
325 get_device(dev);
326 mutex_unlock(&dpm_list_mtx);
327
328 error = suspend_device(dev, state);
329
330 mutex_lock(&dpm_list_mtx);
331
332 /* Check if the device got removed */
333 if (!list_empty(&dev->power.entry)) {
334 /* Move it to the dpm_off list */
335 if (!error)
336 list_move(&dev->power.entry, &dpm_off);
337 }
338 if (error)
339 printk(KERN_ERR "Could not suspend device %s: "
340 "error %d%s\n",
341 kobject_name(&dev->kobj), error,
342 error == -EAGAIN ? " (please convert to suspend_late)" : "");
343 put_device(dev);
344 }
345 mutex_unlock(&dpm_list_mtx);
346 if (error)
347 dpm_resume();
348
349 mutex_unlock(&dpm_mtx);
350 return error;
351}
352
353EXPORT_SYMBOL_GPL(device_suspend);
354
355/**
356 * device_power_down - Shut down special devices.
357 * @state: Power state to enter.
358 *
359 * Walk the dpm_off_irq list, calling ->power_down() for each device that
360 * couldn't power down the device with interrupts enabled. When we're
361 * done, power down system devices.
362 */
363
364int device_power_down(pm_message_t state)
365{
366 int error = 0;
367 struct device * dev;
368
369 while (!list_empty(&dpm_off)) {
370 struct list_head * entry = dpm_off.prev;
371
372 dev = to_device(entry);
373 error = suspend_device_late(dev, state);
374 if (error)
375 goto Error;
376 list_move(&dev->power.entry, &dpm_off_irq);
377 }
378
379 error = sysdev_suspend(state);
380 Done:
381 return error;
382 Error:
383 printk(KERN_ERR "Could not power down device %s: "
384 "error %d\n", kobject_name(&dev->kobj), error);
385 dpm_power_up();
386 goto Done;
387}
388
389EXPORT_SYMBOL_GPL(device_power_down);
390
391void __suspend_report_result(const char *function, void *fn, int ret)
392{
393 if (ret) {
394 printk(KERN_ERR "%s(): ", function);
395 print_fn_descriptor_symbol("%s() returns ", (unsigned long)fn);
396 printk("%d\n", ret);
397 }
398}
399EXPORT_SYMBOL_GPL(__suspend_report_result);